Clear binder calling identity before calling callback

This change clears calling identities before the
onSubscriptionsChangedListener.onSubscriptionsChanged() callback is
made.

Bug: 193731920
Test: atest TelephonyRegistryManagerTest
Change-Id: I21f14e40a05f76346eb90b8f36608b4d6bdf1a29

core/java/android/telephony/TelephonyRegistryManager.java

@@ -111,7 +111,12 @@ public class TelephonyRegistryManager {
         IOnSubscriptionsChangedListener callback = new IOnSubscriptionsChangedListener.Stub() {
             @Override
             public void onSubscriptionsChanged () {
-                executor.execute(() -> listener.onSubscriptionsChanged());
+                final long identity = Binder.clearCallingIdentity();
+                try {
+                    executor.execute(() -> listener.onSubscriptionsChanged());
+                } finally {
+                    Binder.restoreCallingIdentity(identity);
+                }
             }
         };
         mSubscriptionChangedListenerMap.put(listener, callback);